JP6774016B2 - How to make a burner - Google Patents

Description

The present invention relates to a method for manufacturing a burner used in, for example, a combustion device of a hot water supply device.

The applicant has previously proposed, for example, the one described in Patent Document 1 as a specific example of the burner.
The burner described in the same document is a light / light combustion burner, which is a gas burner in which a plurality of deep flame holes and light flame holes are provided on the upper surface portion in order to reduce NOx. This burner has a structure in which a flame hole forming portion and a plate member called a middle plate supporting the flame hole forming portion are housed in a flat burner main body plate having an open upper surface. The above-mentioned constituent members of the burner are formed by pressing a metal plate.

On the other hand, as a constituent member of the burner, for example, there is one provided with a convex portion that bulges into a hemisphere. Conventionally, as a means for forming such a convex portion, there is a means for pressing the metal plate a plurality of times to finish the convex portion stepwise. Specifically, in this means, a convex portion having a size smaller than the convex portion of the final finishing target is formed by the first press working, and the size of the convex portion is increased in the second and subsequent press workings. In this way, a convex portion having a desired shape and size is finally formed.

However, according to the prior art, there is room for improvement, as described below.

That is, when forming the above-mentioned convex portion, it is customary that press working is also performed on other parts of the metal plate at the same time. For this reason, due to the press working of the other portion, the meat of the portion where the convex portion is formed may be pulled toward the other portion, causing a phenomenon (thickness reduction) in which the thickness of the convex portion becomes thin. is there. In recent years, the number of flame holes in the burner tends to be considerably increased, and the thickness of the burner is increasing. For this reason, the drawing of the metal plate during press working is also deepened, and the above-mentioned wall thinning is more likely to occur. Further, when a plurality of press workings are repeated, if the punch for pressing has a center shift in the second and subsequent press workings, the punches abut on the convex portion in a biased manner, which also causes the convex portion to come into contact with the convex portion. The wall thickness becomes thinner. For this reason, conventionally, the wall thickness of the convex portion is considerably thinner than the originally intended size, and there is a possibility that necking or cracking of the convex portion may occur. As a means for suppressing this, it is conceivable to increase the thickness of the metal plate, but adopting such a means is preferable because it causes an increase in manufacturing cost and an increase in the size and weight of the burner. It's not a thing.

Japanese Patent No. 5673965

The present invention has been conceived under the above-mentioned circumstances, and when a convex portion is formed on a component member of a burner by press working, the convex portion is unreasonably thinned. It is an object of the present invention to provide a method for manufacturing a burner capable of preventing the protrusion and appropriately forming the convex portion.

In order to solve the above problems, the following technical measures are taken in the present invention.

In the method for manufacturing a burner provided by the present invention, a metal plate is pressed to produce a burner component having at least one convex portion that bulges substantially hemispherically from a flat plate-like region of the metal plate. It is a method for manufacturing a burner having a step, and in the pressing step, a drawing step of forming a prototype convex portion that bulges substantially hemispherically as a prototype of the convex portion and a drawing step of forming the prototype convex portion are performed. , A molding step of molding into a convex portion having a shape and size that bulges substantially hemispherically as a final finishing target is carried out, and in the drawing step, the prototype convex portion is made higher than the convex portion after molding. It is formed into a material having a high height and a large projected area, and in the molding step, the volume of the prototype convex portion is reduced, and the flat plate-shaped region is formed around the base portion of the convex portion after molding. It is characterized by the appearance of thick-walled parts that are thicker than the peripheral parts .

According to such a configuration, the following effects can be obtained.
That is, the prototype convex portion formed by the drawing step is considered to have a larger volume than the convex portion after molding, and the molding step of the convex portion after molding is performed on the prototype convex portion having a large volume. It is molded as a convex portion having a smaller volume than that of the convex portion. Therefore, when molding the convex portion after molding, the shortage or slight shortage of the meat is eliminated, and even if the meat is pulled by the press working at another part of the metal plate, the thickness of the convex portion is thick. Can be prevented from running out. Further, even if there is some deviation of the center of the punch during the molding process, it is possible to obtain an effect that it is difficult to significantly reduce the wall thickness of a part of the convex portion after molding due to this. For this reason, unlike the conventional technique in which the press working is repeated so as to gradually increase the size of the convex portion, it is possible to secure a sufficient wall thickness of the convex portion after molding. As a result, the strength of the convex portion after molding can be increased, and necking and cracking can be prevented.
Further, the convex portion having a substantially hemispherical bulge shape is likely to cause thinning, and when the wall thickness is reduced, cracking is likely to occur. Therefore, the present invention is particularly suitable for forming a convex portion having such a shape.
Further, the thick-walled portion is a portion caused by a surplus in the meat due to the formation of a convex portion after molding having a size smaller than that in the formed portion of the prototype convex portion. The appearance of such a thick portion means that there is sufficient meat in the convex portion after molding, which is more preferable in order to prevent a shortage in the wall thickness of the convex portion after molding. Become. As a more important effect, even if the meat in the convex region after molding is pulled by the press working at another part of the metal plate, this pull is dealt with by the thick portion. be able to. Therefore, it is possible to obtain the effect of making it difficult for the convex portion after molding to be thinned.

In the present invention, preferably, the drawing step and the molding step are carried out so that the contour size of the thick portion is substantially the same as the contour size of the prototype convex portion.

According to such a configuration, the volume of the thick portion is sufficiently large, and it is more appropriately prevented that the convex portion after molding is thinned due to the press working at other portions. ..

Other features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings.

It is a perspective view which shows an example of the burner to be manufactured of the method which concerns on this invention. It is an exploded perspective view of FIG. It is a main part plan view which shows an example of the manufacturing process of the burner shown in FIG. 1 and FIG. (A) and (b) are cross-sectional views of a main part showing the press working of the convex portion in the manufacturing process shown in FIG.

Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

First, FIGS. 1 and 2 show an example of a burner to be manufactured by the manufacturing method of the present embodiment. The burner B shown in FIGS. 1 and 2 is the same as that described in Patent Document 1, and is a so-called light and shade combustion burner. Since the basic configuration of this burner B is conventionally known, it will be briefly described. That is, the burner B includes a burner main body plate 1, a middle plate 2, a flame hole forming portion 3, and a pair of outer plates 4. The burner main body plate 1 is provided with a pair of side wall portions 10 integrally connected at the lower end portion, and the pair of side wall portions 10 form a flat case shape having an upper surface opening as a whole. Supply ports 11a and 11b for a mixed gas of fuel gas and combustion air are formed on one side of the burner main body plate 1. The flame hole forming portion 3 is a member that forms a plurality of flame holes 5 as a deep flame hole and a light flame hole, and is housed in the burner main body plate 1 together with the middle plate 2. The pair of outer plates 4 are joined to the upper portions of both side surfaces of the burner main plate 1 and form a flame hole 5 (dense flame hole) between the burner main plate 1 and the burner main plate 1.

In the burner B, a plurality of (four in the drawing) convex portions 6 projecting inward are formed at positions near the upper portion of the pair of side wall portions 10 of the burner main plate 1 (see FIG. 2). .. The convex portion 6 serves as an engaging portion or a stopper for preventing the middle plate 2 and the flame hole forming portion 3 from coming off on the burner main body plate 1. The method for manufacturing the burner of the present embodiment is characterized by the above-mentioned step of forming the convex portion 6.

FIG. 3 shows a process of manufacturing the burner main body plate 1 and the pair of outer plates 4 shown in FIG. 2 by pressing the metal plate 7.
The metal plate 7 is, for example, a thin stainless steel plate, which is simplified in the drawing, but is connected in a series in the left-right direction, and the press forming of the burner main plate 1 and the outer plate 4 is a so-called progressive method. It is done using. Further, the burner main body plate 1 and the outer plate 4 are formed in a state of being integrally connected, and are later divided.

In the first region A1 of the press working stage for the metal plate 7, the prototype portion 1B of the burner main plate 1 and the prototype portion 4B of the pair of outer plates 4 are press-molded. In the second region A2, the intermediate molded portions 1A and 4A obtained by further pressing the prototype portions 1B and 4B are formed, and in the third region A3, the burner main plate 1 and the pair of outer plates 4 are pressed. Processing is complete.

In the second region A2, a prototype convex portion 6A that serves as a prototype of the convex portion 6 is formed. The formation of the prototype convex portion 6A is performed as shown in FIG. 4A. Specifically, the process shown in the figure is a drawing step of the metal plate 7 using the punch 9A and the corresponding mold (not shown), and the height of the prototype convex portion 6A formed by this drawing step. Ha is higher than the height H of the convex portion 6 (convex portion 6 after molding) finally formed and shown in FIG. 6B, and the projected area Sa of the prototype convex portion 6A is convex after molding. It is larger than the projected area S of the part 6. The prototype convex portion 6A and the convex portion 6 after molding both have a substantially hemispherical bulging shape.

In the third region A3 of FIG. 3, the molding step for the prototype convex portion 6A shown in FIG. 4A is performed. As shown in FIG. 4B, this molding step is a step of molding the prototype convex portion 6A into the convex portion 6 having the shape and size of the final finishing target. The drawing step and the molding step described above are preferably performed so that the thick portion 60 appears around the convex portion 6 after molding. The thick portion 60 is a portion whose surface is raised above the peripheral surface. More preferably, the drawing step and the molding step described above are performed so that the diameter D of the thick portion 60 (corresponding to the size of the contour in the present invention) is substantially the same as the diameter Da of the prototype convex portion 6A. Is done. Unlike the punch 9 for the forming process, the punch 9A used in the drawing process can adjust the elevating stroke, and by adjusting the drawing amount, the thick portion 60 described above can be made to appear. ..

According to the series of steps described above, since the convex portion 6 having a smaller volume is formed from the prototype convex portion 6A having a large volume, it is possible to prevent the thickness of the convex portion 6 from being insufficient. is there. Since the thick portion 60 appears because the meat of the prototype convex portion 6A exceeds the amount of meat required for molding the convex portion 6, the thick portion 60 is made to appear. If this is the case, it means that there is no shortage in the wall thickness of the convex portion 6.

In the second region A2 and the third region A3 shown in FIG. 3, since various press workings are performed on other parts of the metal plate 7, the prototype convex portion 6A and the prototype convex portion 6A and the part side of the press working part are The flesh of the formed portion of the convex portion 6 may be pulled, but according to the work process of the present embodiment, due to such a situation, the number of the convex portion 6A and the convex portion 6 is significantly reduced. It is possible to make the meat less likely to be produced. Further, even if the meat is pulled from another portion after the convex portion 6 is formed, the meat of the thick portion 60 corresponds to such the pull, and the thinning of the convex portion 6 is preferably prevented. Or it is suppressed. Therefore, according to the present embodiment, it is possible to secure a sufficient wall thickness of the convex portion 6, increase its strength, and prevent necking and cracking from occurring.

The present invention is not limited to the contents of the above-described embodiments. The specific configuration of each step of the burner manufacturing method according to the present invention can be variously changed within the scope of the present invention.

The burner component is generally provided with a plurality of convex portions, but it is not necessary that all of the plurality of convex portions are formed through the drawing step and the molding step intended by the present invention. If at least one of the plurality of protrusions is formed through the drawing step and molding step intended by the present invention, this manufacturing method is included in the technical scope of the present invention.
The convex portion formed by the press working may be provided on the burner component, and the specific shape, size, number, formation position, type of the burner component formed, and the like are not limited .
The specific configuration and use of the burner to be manufactured are not limited.

B Burner 6 Convex part (convex part after molding)
6A Prototype convex part 60 Thick part 7 Metal plate

Claims (2)

A method for manufacturing a burner, which comprises a pressing step of pressing a metal plate to manufacture a burner component having at least one convex portion that bulges substantially hemispherically from a flat plate-like region of the metal plate. There,
In the pressing process, a drawing step of forming a prototype convex portion that bulges substantially hemispherically as a prototype of the convex portion, and a shape and size of the prototype convex portion bulging substantially hemispherically as a final finishing target. Perform the molding process of molding on the convex part of
In the drawing step, the prototype convex portion is formed so as to have a height higher than that of the convex portion after molding and a large projected area .
In the molding step, the volume of the prototype convex portion is reduced, and a thick portion having a plate thickness larger than that of the peripheral portion appears around the base portion of the convex portion after molding in the flat plate-shaped region. A method of manufacturing a burner, which is characterized in that. The method for manufacturing a burner according to claim 1.
A method for manufacturing a burner, wherein the drawing step and the molding step are carried out so that the contour size of the thick portion is substantially the same as the contour size of the prototype convex portion .

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